<?php

/**
 * +----------------------------------------------------------------------+
 * | PHP version 5                                                        |
 * +----------------------------------------------------------------------+
 * | Copyright (C) 2004 MaxMind LLC                                       |
 * +----------------------------------------------------------------------+
 * | This library is free software; you can redistribute it and/or        |
 * | modify it under the terms of the GNU Lesser General Public           |
 * | License as published by the Free Software Foundation; either         |
 * | version 2.1 of the License, or (at your option) any later version.   |
 * |                                                                      |
 * | This library is distributed in the hope that it will be useful,      |
 * | but WITHOUT ANY WARRANTY; without even the implied warranty of       |
 * | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU    |
 * | Lesser General Public License for more details.                      |
 * |                                                                      |
 * | You should have received a copy of the GNU Lesser General Public     |
 * | License along with this library; if not, write to the Free Software  |
 * | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 |
 * | USA, or view it online at http://www.gnu.org/licenses/lgpl.txt.      |
 * +----------------------------------------------------------------------+
 * | Authors: Jim Winstead <jimw@apache.org> (original Maxmind version)   |
 * |          Hans Lellelid <hans@xmpl.org>                               |
 * +----------------------------------------------------------------------+
 *
 * @category Net
 * @package  GeoIP
 * @author   Hans Lellelid <hans@xmpl.org>
 * @license  LGPL http://www.gnu.org/licenses/lgpl.txt
 * @link     http://pear.php.net/package/GeoIP
 * $Id: Location.php 296763 2010-03-25 00:53:44Z clockwerx $
 */

/**
 * This class represents a location record as returned by GeoIP::lookupLocation().
 *
 * This class is primarily a collection of values (the public properties of the class), but
 * there is also a distance() method to calculate the km distance between two points.
 *
 * @category Net
 * @package  GeoIP
 * @author   Hans Lellelid <hans@xmpl.org>
 * @author   Dmitri Snytkine <d.snytkine@gmail.com>
 * @license  LGPL http://www.gnu.org/licenses/lgpl.txt
 * @version  $Revision: 296763 $
 * @link     http://pear.php.net/package/GeoIP
 * @see      GeoIP::lookupLocation()
 */
class GeoIP_Location implements Serializable {

  protected $aData = array(
      'countryCode' => null,
      'countryCode3' => null,
      'countryName' => null,
      'region' => null,
      'regionName' => null,
      'city' => null,
      'postalCode' => null,
      'latitude' => null,
      'longitude' => null,
      'areaCode' => null,
      'dmaCode' => null
  );

  /**
   * Calculate the distance in km between two points.
   *
   * @param GeoIP_Location $loc The other point to which distance will be calculated.
   *
   * @return float The number of km between two points on the globe.
   */
  public function distance(GeoIP_Location $loc) {
    // ideally these should be class constants, but class constants
    // can't be operations.
    $RAD_CONVERT = M_PI / 180;
    $EARTH_DIAMETER = 2 * 6378.2;

    $lat1 = $this->latitude;
    $lon1 = $this->longitude;
    $lat2 = $loc->latitude;
    $lon2 = $loc->longitude;

    // convert degrees to radians
    $lat1 *= $RAD_CONVERT;
    $lat2 *= $RAD_CONVERT;

    // find the deltas
    $delta_lat = $lat2 - $lat1;
    $delta_lon = ($lon2 - $lon1) * $RAD_CONVERT;

    // Find the great circle distance
    $temp = pow(sin($delta_lat / 2), 2) + cos($lat1) * cos($lat2) * pow(sin($delta_lon / 2), 2);
    return $EARTH_DIAMETER * atan2(sqrt($temp), sqrt(1 - $temp));
  }

  /**
   * magic method to make it possible
   * to store this object in cache when
   * automatic serialization is on
   * Specifically it makes it possible to store
   * this object in memcache
   *
   * @return array
   */
  public function serialize() {
    return serialize($this->aData);
  }

  /**
   * unserialize a representation of the object
   *
   * @param array $serialized The serialized representation of the location
   *
   * @return void
   */
  public function unserialize($serialized) {
    $this->aData = unserialize($serialized);
  }

  /**
   * Setter for elements of $this->aData array
   *
   * @param string $name The variable to set
   * @param string $val  The value
   *
   * @return object $this object
   */
  public function set($name, $val) {
    if (array_key_exists($name, $this->aData)) {
      $this->aData[$name] = $val;
    }

    return $this;
  }

  public function __set($name, $val) {
    return $this->set($name, $val);
  }

  /**
   * Getter for $this->aData array
   *
   * @return array
   */
  public function getData() {
    return $this->aData;
  }

  /**
   * Magic method to get value from $this->aData array
   *
   * @param string $name The var to get
   *
   * @return mixed string if value exists or null if it is empty of
   * just does not exist
   */
  public function __get($name) {
    if (array_key_exists($name, $this->aData)) {
      return $this->aData[$name];
    }

    return null;
  }

  /**
   * String representation of the object
   *
   * @return string text and result of print_r of $this->aData array
   */
  public function __toString() {
    return 'object of type ' . __CLASS__ . '. data: ' . implode(',', $this->aData);
  }

  /**
   * Magic method
   * makes it possible to check if specific record exists
   * and also makes it possible to use empty() on any property
   *
   * @param strign $name The name of the var to check
   *
   * @return bool
   */
  public function __isset($name) {
    return (null !== $this->__get($name));
  }

}
